Blind stitch sewing machine



- 4 Sheets-Sheet 1 J. MANN BLIND STITCH SEWING MACHINE Filed Jan. 17,1955 3 wue/wto'b (T055 14 MAN/v L; N Q3 Q m. II, 1936.

- J. MANN BLIND STITCH SEWING MACHINE Filed Jan. 17, 1935 4 Sheets-Sheet2 Feb. 11, 1936.. r MANN I BLIND STITCH SEWING MACHINE Filed Jan. 17,1935 4 Sheets-Sheet "-5 L lb 1 1,52

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BLIND STITCH SEWING MACHINE Filed Jan. 1'7, 1935 4 Sheets-Sheet 4 2 45.15 X- vs U 59; 50

r I E6 55 51 52' 55 54 23 n JbsEPH MAN/V7 Patented Feb. 11, 1936 PATENTOFFICE 2,030,751 BLIND STITCH SEWING MACHINE Joseph Mann,

Philadelphia, Pa.,

assignor to Lewis Invisible Stitch Machine Company, St. Louis, Mo., acorporation of Maine Application January 17, 1935, Serial No. 2,257

15 Claims.

This invention relates to new and useful improvements in blind stitchsewing machines generally, although more particularly to blind stitch,sewing machines employed in hemming operations.

The principal object of the invention is to pro-- vide a blind stitchsewing machine of the single thread chain stitch type for seaming hems,by

a means of which a line of chain stitches will be 6 formed to unite thehem fold to the body fabric, the connecting portions of the threadbetween straight line in parallelism with the inner edge of the hem andthe enchained loops being disby concealed from View.

Another object of the invention is to provide 5 posed under the inneredge of the hem and therea stitch forming mechanism of the typedescribed wherein means are provided for insuring the nee- 20 dleentering its own loop on each penetrating movement of the needle.

With these and other objects in view which will more fully appear, thenature of the invention M will be more clearly understood by thefollowing 5 description, the appended claims and the several viewsillustrated in the accompanying drawings.

In the drawings: Figure 1 is a left hand elevation of a sewing .machineconstructed in accordance with my ingovention,

Figure 2 is a partial top plan View of the left hand end of suchmachine,-

Figure 3 is a front elevation thereof, Figures 4, 5 and 6 are enlargeddetail plan 35 views of the presser foot, the fabric, and the stitchforming mechanism showing the needle and the cooperating non-threadedlooper in different positions in a given cycle,

Figure 7 is a view similar to Figure 4 but with 40 the fabric removed inorder to better disclose the ridge forming element and the work clamp,

Figure 8 is a perspective view of the presser foot, Figure 9 is anenlarged diagrammatic view il- 45 lustrating the relative positions ofthe presser foot, the fabric, the needle, the cooperating looper, andthe ridge forming element when the hem only is being stitched,

Figure 10 is a similar view but showing the 50 ridge forming element inposition when anchor stitches are being formed in the hem and bodyfabric, Figure 11 is a detail view showing a modification of a drivingconnection between the looper 55 and the main shaft, and

Figure l2 is an enlarged plan view of the hem seam constructed inaccordance with my invention.

Like reference numerals designate corresponding parts throughout theseveral figures of the 5 drawings.

My invention is adapted especially for joining a hem A to a body fabricor base layer B by a line of blind stitches, as shown in Figure 12. Theinner edge of the hem is indicated at a, and the 10 hem may have aninturned edge portion a if desired. A single needle thread C is employedto form a line of chain stitches and the needle loops 0 are spacedequidistantly apart. These loops pass downwardly through the hem A at 15points 0', and the connecting portions of the thread between the loopsare arranged in a straight line and in parallelism to the inner edge atof the hem. Certain of these needle loops enter and emerge from theupper face of the body fabric as indicated at c to thereby form anchorstitches D which function to join the hem with the body fabric, whileother needle loops miss the body fabric entirely to thereby formresultant skip stitches E. In the upper portion of Figure 12, I haveillustrated a plurality of successively formed anchor stitches D, and inthe lower portion of this figure, I have illustrated a plurality ofalternately formed anchor stitches D and skip stitches E. It will benoted that the enchained loops are all located between the hem and thebody fabric and that they are'concealed from view by the former. It willbe understood that either all anchor stitches, or alternate anchor andskip stitches, or any combination thereoflmay'be employed in joining ahem to a body fabric.

The machine of my invention includes a base 5 having a standard 8projecting upwardly from the rear right hand corner thereof, an arm 1 40which extends laterally from the upper end of said standard, and an arm8 which extends forwardly from the left hand end of the arm 1. Fixed tothe free end of the arm 8 in the usual manner is a presser foot 9 havinga centrally located and longitudinally. extending opening I 0 formedtherein. Journaled in the laterally extending arm I is a main shaft IIand journaled in the arm 8 is an oscillatory needle shaft l2 which isdriven from themain shaft by'a connection indicated generally at l3. Theneedle shaft I2 is disposed directly above the opening In in the foot,and fixed to the outer end of the shaft is a needle arm l4 carrying acurved needle l5. Thus when the needle shaft I2 is oscillated the asneedle l will reciprocate transverselyacross the opening in the presserfoot. It will be noted 7 at this time that the penetrating stroke of theneedle l5, as viewed from the front of the machine, is from right toleft.

Rigid with the base 5 is a post I6 which is located in a plane inadvance of the standard 6 and pivotally supported on the upper end ofthis post is a work support I1 having a lateral extension l8 whichprojects under the presser foot 9, the work support ll being yieldablyheld against depression by a spring l9.

The mechanism employed for presenting the work to the needle, issubstantially identical with that shown in the application of Charles W.Mueller, filed Jan. 17, 1934, Serial No. 707,023, for improvements inBlind stitch sewing machines; and a general description thereof will besufficient to a clear understanding of my inven' tion. A lower 4-motionfeed dog 20 cooperates with the lower face of the presser foot tointermittently feed the work to the needle. This feed dog isactuatedfrom the'rock shafts 2|, 22 which are journaled on the worksupport I! and are driven by suitable connections from the main shaft H.A vertically yieldable work clamp 23 is also mounted on the work supportand cooperates with the lower face of the foot'to clamp the work againstthe thrust of the needle. Also mounted on the worksupport is avertically reciprocatory ridge forming element or plunger 24 which isactuated by an oscillatory cam 25, the latter being connected to a camshaft 26 jour'naled on the work support" and driven bysuitableconnections from the main shaft, as shownand described in said Muellerapplication. These driving connections are such-that normally theplunger 24 rises to the same height during successivecycles, therebyinsuring the formation of successive anchor stitches D, as shown inFigure 9. These driving connections, however; include a manual controlmeans whereby the plunger will rise to a lesser height during alternatecycles, thereby'insuring the formation of alternate anchor and skipstitches D, E respectively, as shown in Figs. 9 and '10. An upper feeddog I-l, which operates in the opening ll] of the foot-in rear of theneedle path and cooperates with the work clamp23' to engage the hem andfeed thework"rearwardly,-is"fixed to the front end of afeed lever 21pivoted on the needle arm 8, the rear end of 'the lever beingeccentric-connected as'at28 to the main shaft II. An edge guide 29 forthe inner edgea of the hem A, is attached to the front end of the foot 9and is disposed in substantial alinement with'the left hand wall of thepresser foot opening I0.

In order to form the line of singlethr'ead chain stitches, I employ acomplemental stitchforming' mechanism which cooperates with theneedleand includes a loop taker X. As shown in the accompanyingdrawings, this loop taker X is in the 7 form of a non-thread carryinglooper having an arcuate beak 30 and an attaching shank 3|, the latterbeing secured to a holder 32 by a clamp screw 33. The holder 32 isclamped by a screw 34 to the lower end of a vertically disposed rockshaft 35 which is journaled in a bracket 36 at tached to the forward endof the frame arm 8 by screws 31, the shaft 35 and the loop taker X beinglocated above the presser foot 9 and at the left of the opening 10therein. The shaft35 is also disposed in front of the vertical planecontaining the path of needle reciprocations. The beak 30 of the looptaker X extends rearwardly relative totheshank 3| and oscillates in ahorizontal plane above the needle l5. The inner edge 30a.

looper X will oscillate in timed relation thereto.

Fixed to the presser foot 9 by a screw 4| is a looper abutment 42. Thisabutment is located intermediate the looper X and the left wall of thepresser foot opening l0, and the forward end 43 of this abutment islocated at a point slightly in rear of the vertical plane containing thepath of needle travel. Instead of oscillating the looper shaft 35 by themechanism described above, I may employ the construction shown in Figure11 wherein a driving eccentric 44 is fixed to the main shaft l I an'd'aneccentric strap 45 has its rear end engaged with the eccentric 44 andits front end connected to a rock arm 46 fixed to the looper shaft 35.

"In operation, the machine is loaded in the usual manner by firstlowering the work support'an'd inserting the body fabric and hem underthe plunger 24 have been manually controlled for forming successiveanchor stitches D, the needle on its forward or penetrating stroke willenter the upper surface of the hem A at a point spaced from-the inneredge (1 thereof. The needle will then emerge from the lower face of thehem and then enter and emerge from the upper face of the body fabric asshown in Figure 10. The point where the needle enters and emerges fromthe body fabric is under the hem'and in spaced relation to the inneredge a. thereof. As the needle begins to recede it casts out the usualneedle thread loop and the beak 30 of the looper X will enter saidneedle thread loop as shown in Figure 5. As soon as the needle pointwithdraws from the hem, the fabric is fed by the feeding mchanism astitch length distance and during this feed stroke the needle'threadloopwhich is around the looper X is fed rearwardly against the forward end43 of the abutment 42 which functions to maintain the needle loop inopen relation and in the proper position to be entered by the needle onits next for ward strokej By reason of the shaft 35 being located inadvanceof the vertical plane containing the path of needlereciprocations and the inner edge of the looper being concentric to theaxis of the shaft, the beak of the looper will holdthe needle threadloop against slipping off the point of the looper until after the needlehas entered said loop. As soon as the needle has entered this needlethread loopthe looper X withdraws fromsaid loop, and as a result theenchained needle thread loops will lie in a straight line under the hemand in spaced relation to the inner edge 21 thereof. Thus by myinvention, I am enwill be disposed under the inner edge of the hem andthereby concealed from view.

It will be noted that the frame includes a forwardly extending arm 8;that the main shaft I I is journaled in the frame in rear of said arm"8; that the axis of the needle shaft I2 is in parallelism with the majoraxis of the presser foot opening l0, and that the vertical loopershaft35 is oscillated from the main shaft in timed relation to theneedle reciprocations.

It is of course to be understood that the details of structure andarrangement of parts may be variously changed and modified withoutdeparting from the spirit and scope of my invention.

I claim:-

1. In a single thread blind stitch-sewing machine, the combination witha frame including a standard and a laterally extending arm supportedthereby, of a presser foot mounted on said arm and having an opening, athreaded needle mounted on the arm above the foot for reciprocationstransversely across the presser foot opening, a ridge forming elementfor projecting a ridge of fabric upwardly through the opening intoneedle penetrating position, means for intermittently feeding the fabricto the needle, and a nonthreaded loop taker supported on the arm andlocated above the foot and operating entirely on that side of the ridgeforming element opposite the point of needle penetration in. the fabricfor engaging the needle thread loop and holding the same for re-entranceby the needle.

2. In a single thread blind stitch sewing machine, the combination witha frame including'a standard and a laterally extending arm supportedthereby, of a presser foot mounted on said arm and having an opening, athreaded needle mounted on the arm above the foot for reciprocationstransversely across the presser foot opening, a

ridge forming element for projecting a ridge of fabric upwardly throughthe opening into needle penetrating position, means for intermittentlyfeeding the fabric to the needle, and a nonthreaded loop taker supportedon the arm and located above the foot and operating entirely on thatside of the ridge forming element opposite the point of needlepenetration in the fabric for engaging the needle thread loop andholding the same for re-entrance by the needle, said loop taker beingsupported for oscillatory movements about a vertical axis and includinga curved beak movable in a horizontal plane.

3. In a single thread blind stitch sewing machine, the combination witha frame including a standard and a laterally extending arm supportedthereby, of a presser foot mounted on said arm and having an opening, athreaded needle mounted on the arm above the foot for reciprocationstransversely across the presser foot opening, a ridge forming elementfor projecting a ridge of fabric upwardly through the opening intoneedle penetrating position; means for inter: mittently feeding thefabric to the needle, and a non-threaded loop taker supported on the armand located above the foot and operating entirely on that side of theridge forming element opposite the point of needle penetration in thefabric for engaging the needle thread loop and holding the same forre-entrance by the needle, said loop taker being supported foroscillatory movements about a vertical axis located in ad- Vance of thevertical plane containing the path of needle reciprocations andincluding a rearwardly extending curved beak movable in a horizontalplane above the needle.

4. In a single thread blind stitch sewing machine, the combination witha presser foot having an opening, of a threaded needle mounted above thefoot across the presser foot opening, a ridge forming element forprojecting a ridge of fabric upwardly through the opening into needlepenetrating pofor reciprocations transversely sition, means forintermittently feeding the fabric to the needle, a non-threaded looptaker located above the foot and operating entirely on one side of theridge forming element opposite the point of needle penetration in thefabric for engaging the needle thread loop and holding the same forre-entrance by the needle, and anabutment on the foo-t between the looptaker and the ridge forming element for retaining the needle l-oopextending around the loop taker in position for re-entrance by theneedle.

5. In a single thread blind stitch sewing machine, the combination witha presser foot having an opening, of a threaded needle mounted above thefoot for reciprocations transversely across the presser foot opening, aridge forming element for projecting a ridge of fabric upwardly throughthe opening into sition, means for intermittently feeding the fabric to'the needle, a non-threaded loop taker located above the foot andoperating entirely on one side of the ridge forming element opposite thepoint of needle penetration in the fabric for engaging the needle threadloop and holding the same for re-entrance by the needle, said loop takerbeing supported for oscillatory movements about a vertical axis andincluding a curved beak movable in a horizontal plane, and an abutmenton the foot between the loop taker and the ridge forming element forretaining the needle loop extending around the loop taker in positionfor re-entrance by the needle.

6. In a single thread blind stitch sewing machine, the combination witha presser foot having an opening, of a threaded needle mounted above thefoot for reciprocations transverselyacross the presser foot opening,element for projecting a ridge of through the opening into needlepenetrating position, means for intermittently feeding the fabric to theneedle, a non-threaded loop taker located above the foot and operatingentirely on one side of the ridge forming element opposite the point ofneedle penetration in the fabric for engaging the needle thread loop andholding the same for re -entrance by the needle, said loop taker beingsupported for oscillatory movements about a vertical axis located inadvance of the vertical plane containing the path of needlereciprocations and including a rearwardly extending curved beak movablein a horizontal plane above the needle, and an abutment on the footbetween the loop taker and the ridge forming element for retaining theneedle loop extending around the loop taker in position for re-entranceby the needle.

7. In a single thread blind stitch chine,'the combination with a presserfoot having an opening, above the foot for reciprocations transversely,across the presser foot opening, a ridge forming element for projectinga ridge of fabric upwardly through the opening into needle penetratingposition, means for intermittently feeding the faba ridge forming fabricupwardly needle penetrating po-- sewing ma-- of a threaded needlemounted ric to the needle, "a non-threaded loop taker lo cated above thefoot and operating entirely on one side of the ridge forming elementopposite the point of needle penetration in. the fabric and entirelyabove the path of the needle for engaging the needle thread loop andholding the same for re-entrance by the needle, and an abutment' on thefoot between the loop taker and the ridge forming element for retainingthe needle loop extending around the loop taker in position forre-entrance by the needle. r

8. In a single thread blind stitch sewing machine for joining a hem to abody fabric, the combination with a horizontal presser foot having alongitudinallyextending opening therein,

' needle will pass first through the hem and then enter and emerge'fromthe body fabric, means for feeding the fabric: rearwardly to the needle,a movable non-threaded'loop taker located above the foot and operatingentirely on the left side of-the ridge forming element for engaging theneedle thread loop and holding the same for re entrance. by the needle,and means for moving said loop taker in timed relation to the needlereciprocations.

9. In a single thread blind stitch sewing ma-' chine for joining a hemto a body fabric, the combination with a horizontal presser foot havinga longitudinally extending opening therein, a hem guide mounted on thefront end of the foot in substantial alinement with the left wall of thepresser foot opening, of a threaded needle mounted above the foot forreciprocations transversely across the presser foot opening; thepenetrating stroke of the needle being towards the left wall of thepresser foot opening, a ridge forming ele ment for projecting a ridge ofbody fabric and the hem upwardly through the opening into needlepenetrating position wherebylthe needle will pass first through the hemand then enter and emerge from the body fabric, means for feeding thefabric rearwardly to the needle, a movable non-threaded loop takerlocated above the foot and operating entirely on the left side of theridge forming element for engaging the needle thread loopnand holdingthe same for re-entrance by the needle, an abutment located on the footin rear of the path of needle travel and between the loop taker and theridge forming element for retaining the needle loop extending around theloop taker in position for re-entrance by the needle, and means formoving said loop taker in timed relation to the needle reciprocations,

10. In a single thread blind stitch sewing machine for joining a hem'toa body fabricgthecombination with a horizontal presser foot having alongitudinally extending opening therein, a heme guide mounted on thefront end of the foot in substantial alinement withthe left wall of thepresser foot opening, of a threaded needle,

mounted above the foot for reciprocations transversely across thepresser foot opening, the penetrating stroke of the needle being towardsthe left wall of the presser foot opening, :a ridge forming element forprojecting a ridge of body rear of the path of needle travel and betweenthe fabric and the hem upwardly through the, opening into needlepenetrating position whereby the needle will pass first through the hemand then enterjand emergefrom the body fabric, means, for,

feeding the fabric rearwardly to the needle, a 5- V movable non-threadedloop taker located above the foot and operating entirely on the leftside of the ridge forming element for, engaging the needle thread loopand holding the same for reentrance by the needle, said loop taker beingsupported for oscillatory movements about avertical axis: and. includinga curved beak movable in a horizontal plane, andmeans for moving saidloop taker in timed relation to the needle recipro cations. v

11. In a single thread blind stitch sewing ma:-. chine for joining a hemto a body fabric, the com-: bination with a horizontal presser foothaving a longitudinally extending opening therein, a hem guide mountedon the front end of the foot in substantial alinement with the left wallof the presser foot opening, of a threaded needle mounted above the footfor reciprocations transversely across the presser foot opening, thepenetrating stroke of the needle being towards the'left Wall of thepresser foot opening, a ridge forming element for projecting a ridge ofbody fabric and the hem upwardly through the openinginto needlepenetrating position whereby the needle will pass first through the hem'and then enter and emerge from the body fabric, means for feeding thefabric rearwardly to the needle'a movable non-threaded loop takerlocated above the foot and operating entirely on the left side of theridge forming element for engaging the needle thread loop and holdingthe same for re-entrance by the needle, said loop taker; being supportedfor-oscillatory movements about a vertical axis located in a.d-. Vanceof the vertical plane containing the path of needle reciprocations andincluding a rear-' wardly extending curved beak movable in a horizontalplane above the needle, and means for moving said loop taker in timedrelation to the needle reciprocations. V 7

12. In ,a single thread blind stitch sewing machine for joining a hem toa body fabric, the combination with a horizontal presser foot having alongitudinally extending opening therein, a hem guide, mounted on thefront end of the foot in substantial alinement with the left Wall of thepresser foot opening, of a threaded needle mounted above the foot forreciprocations transversely across the presser foot opening, thepenetrating stroke of the needle being towards the left wall of thepresser foot opening, a ridge forming element for projecting a ridge ofbody fabric and theshem upwardly through the opening into needlepenetrating position whereby the needle will pass first through the hemand then enter and, emerge from the body fabric, means for feeding thefabric rearwardly to the needle, a movable non-threaded loop takerlocated above the foot and operating entirely on the left side of theridge forming elementlfor engaging the needle thread loop and holdingthe same for re-entrance s5 by the needle, said loop taker beingsupported for oscillatory movements about avertical axis and includingacurved beak movable in a horizontal plane, an abutment located on thefoot in loop taker and. the ridge forming element for retaining theneedle loop extending around the loop taker in position for re-entranceby the nos dle, and means for moving said loop taker in timed relationto the needle reciprocations.

so A

2,030,751 13. In a single thread blind stitch sewing machine for joininga hem to a body fabric, the combination with a horizontal presser foothaving a longitudinally extending opening therein, a hem uide mounted onthe front end of the foot in substantial alinement with the left wall ofthe presser foot opening, of a threaded needle mounted above the footfor reciprocations transversely across the presser foot opening, thepenetrating stroke of the needle being towards the left wall of thepresser foot opening, a ridge forming element for projecting a ridge ofbody fabric and the hem upwardly through the opening into needlepenetrating position whereby the needle will pass first through the hemand then enter and emerge from the body fabric, means for feeding thefabric rearwardly to the needle, a movable non-threaded loop takerlocated above the foot and operating entirely on the left side of theridge forming element for engaging the needle thread loop and holdingthe same for re-entrance by the needle, said loop taker being supportedfor oscillatory movements about a vertical axis located in advance ofthe vertical plane containing the path of needle reciprocations andincluding a rearwardly extending curved beak movable in a horizontalplane above the needle, an abutment located on the foot in rear of thepath of needle travel and between the loop taker and the ridge formingelement for retaining the needle loop extending around the loop taker inposition for re-entrance by the needle, and means for moving said looptaker in timed relation to the needle reciprocations.

14. In a single thread blind stitch sewing machine, the combination witha frame including a base and a forwardly extending arm, of a horizontalpresser foot fixed to the forward end of said arm and having alongitudinally extending opening, a Work support located under the foot,a main shaft journaled in the frame in rear of the forwardly extendingarm, an oscillatory needle shaft journaled in the forwardly extendingarm and having its axis in parallelism with the major axis of thepresser foot opening, a needle arm fixed to the forward end of theneedle shaft, a threaded needle fixed to said needle arm forreciprocations entirely above and across the presser foot opening, aridge forming element mounted on the work support for projecting a ridgeof fabric upwardly through the presser foot opening into needlepenetrating position, means for feeding the work rearwardly to theneedle, a vertically disposed rock shaft supported on the forward end ofsaid forwardly extending frame arm, a nonthreaded loop taker fixed tothe lower end of the rock shaft for engaging the needle loop and holdingthe same for re-entrance by the needle, and actuating connectionsbetween said rock shaft and the main shaft for oscillating the former intimed relation to the needle reciprocations.

15. In a single thread blind stitch sewing machine, the combination witha frame including a base and a forwardly extending arm, of a horizontalpresser foot fixed to the forward end of said arm and having alongitudinally extending opening, a work support located under the foot,a main shaft journaled in the frame in rear of the forwardly extendingarm, an oscillatory needle shaft journaled in the forwardly extendingarm and having its axis in parallelism with the major axis of thepresser foot opening, a needle arm fixed to the forward end of theneedle shaft, a threaded needle fixed to said needle arm forreciprocations entirely above and across the presser foot opening, aridge forming element mounted on the work support for projecting a ridgeof fabric upwardly through the presser foot opening into needlepenetrating position, means for feeding the work rearwardly to theneedle, a vertically disposed rock shaft supported on the forward end ofsaid forwardly extending frame arm, a non-threaded loop taker fixed tothe lower end of the rock shaft for engaging the needle loop and holdingthe same for re-entrance by the needle, actuating connections betweensaid rock shaft and the main shaft for oscillating the former in timedrelation to the needle reciprocations, and an abutment on the footbetween the loop taker and the ridge forming element for retaining theneedle loop extendin around the loop taker in position for re-entranceby the needle.

JOSEPH MANN.

